Investigating Influential Factors for Commercial Vehicle Crashes Using a Hierarchical Model: Focusing on the Occupational Driver’s Intrinsic Factors

Abstract

The effects of driver-related factors account for more than 90% of the causes of crashes. In particular, drivers of commercial vehicles, i.e., occupational drivers, with long travel distances and hours, require a systematic management system for the driver-related factors. Therefore, occupational driver’s intrinsic factors that have a fundamental influence on the causes of crashes, such as drowsy driving, violation of laws, and reckless driving, must be explored and utilized to lead to effective countermeasures. This study classifies the intrinsic factors into the living environment, health characteristics, working conditions, and company characteristics and develops hierarchical logistic regression models to screen the intrinsic factors affecting crash occurrence. This study focuses on corporate taxis and intercity buses, and survey data on intrinsic factors and transport worker system data are integrated and utilized for 1,060 corporate taxi drivers and 1,005 intercity bus drivers. As a result, it is found that job-related stress and fatigue statistically significantly increase the risk of taxi and bus crashes. In buses, excessive driving schedules and lack of safety training by companies affect the crash occurrence. In taxis, health characteristics such as endocrine and cerebrovascular diseases and elderly drivers are analyzed as significant risk factors. Finally, based on the intrinsic factors derived from this study, we suggest implications and countermeasures for drivers of commercial vehicles.